jQuery Grid Plugin - jqGrid

Hi, I've just found a bug in IE with virtual scrolling.

I'am using:

- IE 9

- jqGrid 4.4.0

- jquery-ui-1.8.2.2

and the following grid-setup:

jQuery("#myTable").jqGrid({
    url: "/Data/RetrieveData",
    mtype: 'POST',
    datatype: "json",
    rowNum: 50,
    jsonReader:{
    root:"invdata",
    page:"currpage",
    total: "totalpages",
    records: "totalrecords" },
    scroll: 1,
    scrollTimeout: 0,
    loadonce: false,
    colModel: [{name:'Property1', index:'Property1', sortable: true, align: 'left'}, {name:'Property2', index:'Property2', sortable: true, align: 'right'}, {name:'Property3', index:'Property3', sortable: true, align: 'left', formatter: 'integer'}, {name:'Property4', index:'Property4', sortable: true, align: 'left', formatter: 'checkbox'}],
    multiselect: true,
    forceFit: true,
    prmNames: {"page":"RequestedPage","rows":"RowCount","sort":"SortingColumn","order":"SortingOrder","search":"",

"nd":"","id":"","oper":"","editoper":"","addoper":"","deloper":"","subgridid":"","npage":"4″,"totalrows":""},
    sortable: true,
    postData: {data: someData}//I'am posting some valid data to my MVC-Controller
});

As you can see, I'am using virtual scrolling. The server ("/Data/RetrieveData") uses the customized prmNames and sends the requested data. Everything works fine, but there is a problem in the Internet Explorer:

The scrolling by mousewheel or by the scrollbar doesn't work, if the Browser is showing a horizontal scrollbar (i. e. if you add an element wich is wider than the browser-window and not using overflow:auto).

It seems as if the reload by ajax resets the scrolling-status. So I tried to reproduce the bug with local data(i. e. data: [...], datatype: "local"): in that case, the scrolling works just fine.

Regards

Sebastian